Not applicable.
Not applicable.
This invention relates to racks for cups and glasses that are used in commercial automatic dishwashers.
It is common in the restaurant and food service industry to use automatic dishwashers for cups and glasses which accept a standard dishwasher rack that is approximately 20xe2x80x3xc3x9720xe2x80x3 square. Different racks are used with different size compartments to most closely match the diameter of the glasses or cups being washed. For tall items, extenders having the same number of compartments are stacked on top of the rack, as is well known in the industry. It is also common to increase wall height by stacking multiple extenders together.
Extenders are joined to the base racks by pin and socket connections along their perimeters. More specifically, each extender has downwardly extending pins at the bottom that fit inside upwardly opening sockets at the top of an adjacent rack or extender. The pins of the adjacent extender align with and fit into the openings in the sockets in the adjacent lower rack or extender, thereby rigidly connecting each piece to create a solid stack. This pin and socket connection is advantageous because the pins and sockets can be formed integrally with the ordinarily injection molded plastic racks and extenders during molding such that separate hardware is not needed.
A significant problem with this technique, however, is shearing of the pins. This can result in damage not only to the stack but the glassware contained therein. To reduce or prevent this occurrence, current practice is to select a high grade plastic resin with good strength characteristics. Of course, this resin is more expensive than lesser grades, and because the pins and sockets are molded as one with the rest of the racks and extenders, this increases the cost considerably.
The invention provides an improved rack extender with a high strength pin construction for connection to a rack used to hold glasses or cups in an automatic dishwasher. Specifically, the extender has a rectilinear frame with four side walls defining a first perimeter edge and a second perimeter edge. The frame includes connector pins spaced apart along and extending from the first edge substantially perpendicularly to the plane defined by the frame. Each pin has a shaft, at least a portion of which tapers inwardly from the first edge, and an enlarged head defining a catch surface. Sockets are spaced apart along the second edge of the frame in alignment with the pins. Each socket opens upwardly in the upper edge of the frame and is sized to receive the shaft and engage the catch surface of a pin.
In one preferred form, the pins are at a bottom side of the frame and the sockets are at the top side of the frame. Also, the frame is square and has four pins and four sockets at each side wall. Each pin shaft has a non-tapered portion between the taper and the head. The head of each pin is tapered and defines an elliptical arc that sweeps 180 degrees.
The improved extender can also have a compartment grid spanning the frame to define openings sized to accommodate the glasses and cups.
The invention also provides an automatic dishwasher rack and rack extender assembly. The rack has side walls with an upper edge having spaced apart upwardly opening sockets. The extender has side walls with a lower edge defining connector pins each having a shaft, at least a portion of which tapers inwardly from the lower edge, and an enlarged head defining a catch surface. The extender is connected to the rack by inserting the pins into the sockets in the rack such that the shaft is disposed within the socket and the head catch surface engages an underside of the upper edge of the side wall.
Other objects and advantages of the invention will be apparent from the detailed description and drawings.